Imipenem/cilastatin possesses a very broad spectrum of antibacterial activity that encompasses the range of Gram-negative and Gram-positive aerobes and anaerobes usually associated with intra-abdominal and other
polymicrobial infections. Its therapeutic efficacy is comparable to that of
aminoglycoside/antianaerobe combination regimens, and the most commonly reported adverse effects are similar to those of other
beta-lactam antibacterials and are generally of a non-serious nature. The acquisition cost of
imipenem/cilastatin is generally greater than that of
aminoglycoside/antianaerobe combination regimens, but treatment with the latter incurs the additional costs of multiple
intravenous administration,
aminoglycoside pharmacokinetic and other monitoring, and possible nephrotoxicity and
ototoxicity. The available pharmacoeconomic studies show a trend towards lower total treatment costs with
imipenem/cilastatin compared with
gentamicin plus
clindamycin. Results from other sources suggest that
imipenem/cilastatin may achieve further cost savings through reduced duration of hospitalisation. Although further study is required to confirm these trends, it appears that the total treatment cost of
imipenem/cilastatin does not exceed that of usual combination
therapy and the risk of
aminoglycoside-induced toxicity is avoided.